Ambac Financial Group will not be filing its Form 10-K on or prior to March 31.
The company cited "significant events" that are described in its Form 8-K filed with the Securities Exchange Commission on March 25. Because of the said events, the insurance firm is revising its Form 10-K to address the effects of these events on its financial statements and disclosure.
Ambac expects that it will be filing its Form 10-K as soon as it has made all of the necessary revisions.